Written report discussing the purity of my aspirin sample I produced. When I carried out the experiment to produce an aspirin sample I had to take a few results I had gained from carrying out the experiment later used these to work out the experimental error and percentage % yield. The results I used where the published value of what temperature pure aspirin melts at, the temperature my aspirin sample melted at, the weight of pure aspirin and the weight of impure aspirin. Firstly I worked out the experimental error by using this equation:
The reason I had 5.83% of error in my experiment is due to some of the errors I could have made whilst conducting it such as measuring out too much or too little of the salicylic acid (tablets) I measured approximately 6g into 100ml conical flask, the experimental error could have been weighing out 6.1g or less than 6g. Other ways in which I could have made experimental error are adding too much or too little ethanoic anhydride as well as the sulphuric acid that was also added to the mixture. In part 2 of the experiment I had to measure out 15cm3 of ethanol, which I could have measured out incorrectly could have been one of the possibilities to cause an increased a experimental error, when I added the crude aspirin to the ethanol if I didn’t boil them at a constant temperature of 75oc, if I let them temperature rise or fall out of limits it could lead to a higher percentage of experimental error. Secondly I worked out my percentage yield:
Weight of impure aspirin = 9.8g
Weight of pure aspirin = 4.83g
The main reasons in which I could have produced a low percentage yield and experimental error are mainly due to the calibration of equipment and how accurately they measure, if the equipment isn’t calibrated well then this will affect the accuracy of certain reading you take from it, if you calibrate it properly your results will be a lot more accurate.
Some of the factors that affect the purity are any impurities that...
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